I may be getting a new TV soon and I haven't bought one in a while so I thought I'd ask the experts in here the questions I have.

This may be a dumb question, but here goes. I was at Sears the other day looking at their TV's. They had several 50"+ HD TV's for around the $1400-$1800 price range. They also had several plasma TV's in this size range priced from around $3500-$6500. Paying particular attention to picture quality, I noticed the big screen TV's had just as nice of a picture as the Plasmas had. Is the price of the plasmas so much higher than the big screen TV's simply because they come in so much smaller of a package? Granted, it would be nice to hang a plasma on the wall, but my living room is plenty big enough for a regular big screen TV and I can't see how a plasma would be worth 2-3 more money just because of its size. Now if its picture quality was a lot better as well, then maybe I could justify the price difference, but just because it's smaller doesn't warrant the much higher price. Is size the only difference between a plasma and a regular HD big screen TV?

Also, what's the best big screen non-plasma HD TV available? Thanks.